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  <title>Portable file locking</title>

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</div><hr /><div id="splfileobject.flock" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">SplFileObject::flock</h1>
  <p class="verinfo">(PHP 5 &gt;= 5.1.0)</p><p class="refpurpose"><span class="refname">SplFileObject::flock</span> &mdash; <span class="dc-title">Portable file locking</span></p>

 </div>

 <div class="refsect1 description" id="refsect1-splfileobject.flock-description">
  <h3 class="title">说明</h3>
  <div class="methodsynopsis dc-description">
   <span class="modifier">public</span> <span class="type">bool</span> <span class="methodname"><strong>SplFileObject::flock</strong></span>
    ( <span class="methodparam"><span class="type">int</span> <code class="parameter">$operation</code></span>
   [, <span class="methodparam"><span class="type">int</span> <code class="parameter reference">&$wouldblock</code></span>
  ] )</div>

  <p class="para rdfs-comment">
   Locks or unlocks the file in the same portable way as <span class="function"><a href="function.flock.html" class="function">flock()</a></span>.
  </p>
 </div>


 <div class="refsect1 parameters" id="refsect1-splfileobject.flock-parameters">
  <h3 class="title">参数</h3>
  <p class="para">
   <dl>

    
     <dt>
<em><code class="parameter">operation</code></em></dt>

     <dd>

      <p class="para">
       <em><code class="parameter">operation</code></em> is one of the following:
       <ul class="itemizedlist">
        <li class="listitem">
         <span class="simpara">
          <strong><code>LOCK_SH</code></strong> to acquire a shared lock (reader).
         </span>
        </li>
        <li class="listitem">
         <span class="simpara">
          <strong><code>LOCK_EX</code></strong> to acquire an exclusive lock (writer).
         </span>
        </li>
        <li class="listitem">
         <span class="simpara">
          <strong><code>LOCK_UN</code></strong> to release a lock (shared or exclusive).
         </span>
        </li>
        <li class="listitem">
         <span class="simpara">
          <strong><code>LOCK_NB</code></strong> to not block while locking (not supported on Windows).
         </span>
        </li>
       </ul>
      </p>
     </dd>

    
    
     <dt>
<em><code class="parameter">wouldblock</code></em></dt>

     <dd>

      <p class="para">
       Set to <strong><code>TRUE</code></strong> if the lock would block (EWOULDBLOCK errno condition).
      </p>
     </dd>

    
   </dl>

  </p>
 </div>


 <div class="refsect1 returnvalues" id="refsect1-splfileobject.flock-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   成功时返回 <strong><code>TRUE</code></strong>， 或者在失败时返回 <strong><code>FALSE</code></strong>。
  </p>
 </div>


 <div class="refsect1 examples" id="refsect1-splfileobject.flock-examples">
  <h3 class="title">范例</h3>
  <p class="para">
   <div class="example" id="example-3861">
    <p><strong>Example #1 <span class="methodname"><strong>SplFileObject::flock()</strong></span> example</strong></p>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$file&nbsp;</span><span style="color: #007700">=&nbsp;new&nbsp;</span><span style="color: #0000BB">SplFileObject</span><span style="color: #007700">(</span><span style="color: #DD0000">"/tmp/lock.txt"</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"w"</span><span style="color: #007700">);<br />if&nbsp;(</span><span style="color: #0000BB">$file</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">flock</span><span style="color: #007700">(</span><span style="color: #0000BB">LOCK_EX</span><span style="color: #007700">))&nbsp;{&nbsp;</span><span style="color: #FF8000">//&nbsp;do&nbsp;an&nbsp;exclusive&nbsp;lock<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">$file</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">ftruncate</span><span style="color: #007700">(</span><span style="color: #0000BB">0</span><span style="color: #007700">);&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #FF8000">//&nbsp;truncate&nbsp;file<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">$file</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">fwrite</span><span style="color: #007700">(</span><span style="color: #DD0000">"Write&nbsp;something&nbsp;here\n"</span><span style="color: #007700">);<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">$file</span><span style="color: #007700">-&gt;</span><span style="color: #0000BB">flock</span><span style="color: #007700">(</span><span style="color: #0000BB">LOCK_UN</span><span style="color: #007700">);&nbsp;&nbsp;&nbsp;</span><span style="color: #FF8000">//&nbsp;release&nbsp;the&nbsp;lock&nbsp;&nbsp;&nbsp;&nbsp;<br /></span><span style="color: #007700">}&nbsp;else&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;echo&nbsp;</span><span style="color: #DD0000">"Couldn't&nbsp;get&nbsp;the&nbsp;lock!"</span><span style="color: #007700">;<br />}<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

   </div>
  </p>
 </div>


 <div class="refsect1 seealso" id="refsect1-splfileobject.flock-seealso">
  <h3 class="title">参见</h3>
  <p class="para">
   <ul class="simplelist">
    <li class="member"><span class="function"><a href="function.flock.html" class="function" rel="rdfs-seeAlso">flock()</a> - 轻便的咨询文件锁定</span></li>
   </ul>
  </p>
 </div>


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